Study On Synthesis And Industrialization Of Antioxidant RD With Superior Quality

Antioxidant RD is one of the most important rubber auxiliary materials of Nanjing Chemical Plant. It is in important position in this industry, NCP benefits a lot from it. But its effective content (TMDQ's dimmer, trimer, tetramer) is less and harmful content (such as isopropyl bis aniline) is higher than foreign product. Some tire manufactures at home and abroad hope NCP improve RD's quality, for example Michelin demanded that isopropyl bis aniline must be less than 0.4% in its purchasing specification.Two methods have been adopted to produce superior quality goods. One is applying"two-step process", but the equipment investment is too expensive for the long technical process. The other is applying"one-step process", but the catalyst used in this process is expensive. The cost is high-priced when the above two methods be applied. In order to meet the demands of customers, the study on synthesis of antioxidant RD with superior quality was determined. The main task is to discover the optimum conditions by applying"one-step process"with the catalyst of self-supplying hydrochloric acid, then turn them into industrialization.The main reaction of the synthesis of antioxidant RD, the condensation and polymerization of acetone and aniline is studied to discover the optimum conditions by applying"one-step process"with the catalyst of hydrochloric acid. Based on the present 2600t/a antioxidant RD equipment. The middle-scale test is processed to verify the optimum conditions and provide the relative solutions on problems appeared in the experiment.The detailed design of 6000t/a new equipment is provided, according to the established optimum conditions, middle-scale test results and production experience of present equipment. Furthermore, batch operation is applied in the reaction section and the continual operation is applied in separation section. The mass and heat balance of every stage, technology calculation and structure design of main equipment are also included. The way of heating and structure of agitator for main reactor are improved. The process for acetone's recovery is modified too.Presently, the commission of the new equipment of 6000t/a is successful. The capacity is more than 20t per day. The quality of antioxidant RD improves greatly and meets the demands of customers well. The mole ratio between acetone and aniline is reduced from 6:1 to 5:1 for the improvement of main reactor. The consumptions are reduced as well. The cost is reduced by 429.00RMB per ton.